Grantee Research Project Results
2024 Progress Report: Unlocking the Nationwide Potential of Water Reuse
EPA Grant Number: R840462Title: Unlocking the Nationwide Potential of Water Reuse
Investigators: Bloxom, Lyndsey , Linden, Karl G. , Dickenson, Eric , Cath, Tzahi , Hacker, Miriam
Institution: Water Research Foundation , Southern Nevada Water Authority , University of Colorado at Boulder , Colorado School of Mines , University of Pennsylvania
EPA Project Officer: Ludwig-Monty, Sarah
Project Period: September 1, 2022 through May 7, 2025
Project Period Covered by this Report: September 1, 2023 through August 31,2024
Project Amount: $3,245,999
RFA: NATIONAL PRIORITIES: WATER INNOVATION, SCIENCE, AND ENGAGEMENT TO ADVANCE WATER REUSE (2021) RFA Text | Recipients Lists
Research Category: Water Quality , Water , Water Treatment
Objective:
The overall goal of this project is to improve public health protection through the development of quantitative data on the removal of human enteric viruses by treatment processes where wastewater is the source water. This data can be used by the water sector, communities, and regulators to provide log reduction values (LRV) to meet desired risk goals.
Progress Summary:
During this reporting period, the team conducted sampling from five participating utilities across the United States. Samples were collected after each step in the treatment process. Data on coliphages is usually obtained within 24 hours, whereas data for the human culturable viruses takes 3-4 months. Physicochemical parameters are also measured for each sample, and these include the following: water turbidity, pH, conductivity, temperature, UV absorbance at 254 nm, ion analysis (sodium, potassium, calcium, magnesium), and organic analysis including dissolved organic carbon (DOC) size fractions and concentrations.
Our data continue to indicate that infectious coliphage (Somatic Coliphage and F+ Coliphage) may be potentially useful indicators for both assessment of LRVs and the monitoring of treatment processes. Four significant findings to date are as follows:
- Naturally occurring (indigenous) coliphages continue to appear as useful conservative indicators for determining LRV of human viruses during advanced treatment and managed aquifer recharge treatment. Because of the greater concentrations of somatic coliphages compared to male-specific coliphages, the former are often detected in equal or greater concentrations after treatment.
- Naturally occurring somatic coliphages demonstrate reductions throughout the various treatment processes, even after reverse osmosis and advanced oxidation processes. We assay from 110 to 400 liters equivalent volumes of water after advance treatment for coliphage. This allows us to determine a 9 to 10 log reduction of coliphage throughout the treatment process. Again, the coliphage decrease after each treatment step, but the reduction generally becomes less with each treatment step, suggesting that the more resistant viruses are being selected for with each treatment step. Additionally, naturally occurring coliphage may be more resistant than laboratory strains, such as MS2 and phiX-174, which have been used in the past to assess virus removal. This suggests that laboratory-grown coliphages may not accurately reflect the removal of naturally occurring coliphages and human enteric viruses.
- Infectious reoviruses were detected for the first time in groundwater at a managed after recharge site. This suggests that these viruses persist through the treatment processes and may be used for QMRA and regulatory purposes.
- The A549 cell line performs better for detection of infectious virus isolations than the BGM cell line.
- Indigenous coliphages, reoviruses, and adenoviruses appear more resistant to removal processes than laboratory strains. The use of laboratory strains of viruses may underestimate LRV by treatment processes.
Future Activities:
- Continue collecting samples at participating utilities and conducting cell culture assay for human pathogenic viruses.
- Assay larger equivalent volumes of samples both for the coliphages and human viruses.
- Continue conducting engineering scale tests to validate potential LRV under controlled conditions.
Journal Articles:
No journal articles submitted with this report: View all 3 publications for this projectSupplemental Keywords:
Water Reuse, Risk Assessment, Viruses, Surrogate, TreatmentRelevant Websites:
WRF 4955 - Indicator Viruses for Advanced Physical Treatment Process Performance Confirmation Exit
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.